The invention relates to an arrangement for recognizing undesirable particles, especially trash particles, neps, husk neps, burls and the like, in textile fibre material, for example cotton, synthetic fibres and the like, especially on spinning preparation machines, in which the detection of the undesirable particles is effected by optoelectronic means, the fibre material being detectable by a recognition device and the measurement results being supplied to an image-processing device.
In a known arrangement (DE 39 28 279 A), a fibre web is formed in which the fibres are connected with one another in the form of a web. The fibre web is moved in one direction, a sensor registering each undesirable particle stepwise. Because the web is a closed structure and is being moved in only one direction during the detection, it is possible to obtain information as to the nature and amount of the undesirable particles, but not a differentiated view in respect of the processing of the fibre material on the spinning preparation machine.